Leaf mulcher having a suction feed and a centrifugal pulverizer



March 6, 1956 R; I. BEERS 2,737,003

LEAF MULCHER HAVING A SUCTION FEED QND'A-CENTRIFUGAL PULVERIZER 72INVENTOR.

| 1 Rome [.aesns ATTORNEYS March 6, 1956 R. L. BEERS 2,737,003 LEAFMULCHER HAVING A SUCTION FEED AND A CENTRIFUGAL PULVERIZER Filed April20, 1953 2 Sheets-Sheet 2 U INVENTOR.

y ROYCE LBEERS B (0W, W 1

ATTORNEYS United States Patent LEAF MULCHER HAVING A SUCTION FEED AND ACENTRIFUGAL PULVERIZER Royce L. Beers, Birmingham, Mich.

Application April 20, 1953, Serial No. 349,658

4 Claims. (Cl. 55-62) This invention relates to apparatus forpulverizing and for transferring relatively light solid particles, andmore particularly to a mulcher for leaves and the like.

One object of the invention is to provide apparatus for transferringmaterials, such as leaves and the like, from one location to another,having means for breaking up and pulverizing the material to alford amore efficient transfer thereof and also, in the case of certainmaterials which have valuable fertilizing properties, to reduce the sameto a form more convenient for spreading.

The leaf mulcher may be mounted on a carriage so as to be convenientlymovable over the ground, and may comprise a housing having an opening inthe bottom through which the leaves are drawn by a suitable impeller. Itis a further object of the invention to provide means for breaking upand pulverizing material drawn through the housing.

Another object of the invention is to provide the impeller with portionsshaped to have a beating action upon the material which is drawn throughthe housing by the action of the impeller.

Still another object of the invention is to provide bafie means ordeflectors for improving the efilciency of the impeller and fordirecting the flow or circulation through the housing and past the meansfor pulverizing the material.

Other objects of the invention will become apparent as the followingdescription proceeds, especially when taken in connection with theaccompanying drawings wherein:

Figure 1 is a top plan view of the apparatus embodying the presentinvention;

Figure 2 is a side elevational view of the apparatus shown in Figure 1;

Figure 3 is a rear view of the apparatus with parts removed;

Figure 4 is an elevational view of the apparatus with the housing insection to show the interior construction to advantage, the sectionbeing taken along the line 4-4 on Figure 1;

Figure 5 is a view partly in section taken along the line 5-5 on Figure4;

Figure 6 is a top plan view of one of the impeller blades;

Figures 7 and 8 are respectively top plan and side elevational views ofanother impeller blade; and

Figure 9 is a detail sectional view showing the connection between thedrive means and impeller.

Referring now more particularly to the drawings and especially Figures 1and 2 thereof, the device will be seen to comprise a carriage generallyindicated at it}, having a plurality of ground engaging wheels 12.Brackets 14 are secured to the upper side of the carriage near the rearend thereof and respectively pivotally support the rearwardly extendingarms 16, the latter converging in a rearward direction and being securedtogether near their rear extremities by welding or other suitable means,as indicated at 18. The rear extremities of arms 16 are turned outwardlyto provide handle portions 20 respectively capped by suitable hand grips22. The arms 16 may be maintained at a suitable inclination for handoperation of the carriage by a rod 24 engageable with a transversemember 26 interconnecting the arms 16 at an intermediate point. Thefront end of rod 24 is pivotally mounted on the top side of the carriage10 by a bracket 28.

The carriage 10 is in the form of a metal shell having parallel oppositeside walls 30 formed with apertures 32 for receiving the wheelsupporting axles. The top wall 34 of the shell has a central opening 36for accommodating parts of the drive mechanism for an impeller describedmore fully hereinafter.

Within the shell-like carriage is supported a housing 38 through whichthe leaves or like material are caused to flow by the action of theimpeller and in which the breaking up or pulverizing of the material iseffected. The housing 38 comprises a circular side wall 39 which issecured to the side walls 30 of the carriage by nut and bolt assemblies49. The bottom wall of the housing is in the form of an annular ring 42defining a central circular inlet opening 44. An upstanding flange 46extends around the outer periphery of the ring 42 and is secured to theside walls 30 and 39 of the carriage and housing by the nut and boltassemblies 49. The top wall 34 of the carriage within the confines ofthe housing side wall 39 defines the upper limit of the housing 38.

Breaker lugs 48 project radially inwardly from the circular side wall 39of the housing in circumferentiallyspaced relation and have dependingflanges secured to side wall 39 by nut and bolt assemblies 4%! and 50.These breaker lugs 48 are positioned between the bottom wall or ring 42of the housing and the top wall 34 and support an annular ring 52 bymeans of nut and bolt assemblies 54. The rings 42 and 52 will be seen tobe arranged in vertically-spaced concentric relation and the centralcircular opening 56 defined by ring 52 is of approximately the samediameter as that of opening 44 in the bottom wall.

An impeller generally indicated at 58 is supported within housing 38between the rings 42 and 52 and is driven by a suitable motor, such asthat indicated at 60. The motor 69 is supported on the top wall 34 ofthe carriage above the opening 36 therein by a plurality of nut and boltassemblies 62. The output shaft 64 of the motor projects into housing 33centrally of the openings 44 and 56 and normal thereto.

A sleeve 66 (Figure 9) has a circular recess therein for receiving thelower end of the output shaft 64. The sleeve is secured thereto againstrelative axial movement by a bolt 68, and is also keyed against relativerotation.

The impeller blades 70 and '72 are formed with central apertures 74 and76 which receive the lower reduced end portion 78 of sleeve 66 and areclamped against the circular shoulder 80 on said sleeve by the head 32of bolt 68. Friction fiber discs 84 are sleeved over the reduced endportion 78 of the sleeve on opposite sides of the blades 76 and 72 andinterposed between the head 82 of the bolt and the lower fiber disc area rubber washer 86 and a steel washer 88. The blades are thusoperatively connected to the output shaft 64 of the motor for rotationas aunit therewith. A circular disc 90 is also sleeved over the reducedend portion 78 of the sleeve between theblades and the blades and disc9t) are rigidly interconnected by nut and bolt assemblies 92.

Referring now to Figures 4, 5, 7 and 8, the blade 70 will be seen tocomprise a central horizontal portion 94 having the horizontalextremities 96 disposed somewhat below the central portion 94 andconnected to the latter by the inclined intermediate portions 98. Theleading edges of the extremities 96 are bevelled as shown at 100 andthese bevelled edges provide cutting surfaces for cutting grass. Thetrailing edges of the extremities 96 are inclined upwardly as shown at l2 to provide a lifting action which tends to draw air and grass orleaves and the like upwardly into the housing upon rotation of blade 79in the direction indicated by the arrow in Figure 5.

Referring to Figures 4-, 5 and 6, the blade 72. comprises a main bodyportion which extends in a common plane throughout its horizontalextent, and the opposite trailing edges of the blade 72 are formed v thvertically upturned flanges M35. These flanges oonerate v th the edges)6 of blade 7t) in directing the ci X and entrained solid particlesupwardly, and also have a beating action upon the leaves tendi .g tobreak them up by direct impingement and also by creating a turbulence ofair.

The rotation of the blades 7%? am 72 flow about the axis of rotationcausing the air and s particles to move outwardly by centrifugal forceage.v the circular side wall 39 of the housing. In this connection itwill be noted that a plurality of breaker pins 1&8 project radiallyinwardly from the side wall 39 at circumferentially-spaced intervals andthese pins are ei'lective to break up and pulverize the leaves or like iaterial impinging thercagainst. in the present instance, these pins areactually formed by the shanks of the securing means ill and 5%.

The disc 9i) will be seen to extend across the openings 44 and 56 and tobe of approximately the same diameter as these openings. This discprovides a partial shield between the openings 44 and 56 and serves todirect the incoming air to the radially outward portions of the housing,preventing the air and entrained particles from bypassing the breakerpins breaker lugs In the upper portion of housing 33 above ring 5'2, thec'n'cular side wall 3? is formed with an opening which opens into anoutlet passage for discharge through the outlet opening 11?. in thehousing. A lip 113 projects beyond the lower edge of opening 31?. and issli htly upturned to spread the material discharge over a wide area.

The operation of the leaf mulcher will now be readily apparent. When themotor 61% is in operation, the blades 79 and '72 are rotated producingan updraft by the action of the upturned portions M2 and on the trailingedges of the blades. Leaves and other relatively light material maythereby be drawn into the housing in a cur rent of air directed to theradially outward portions of the housing by the central disc 93'. Theair and entrained particles are urged radially outwardly by centrifugalforce caused by the rotary motion of the impeller, and the solidparticles are broken up and pulverized by striking against the breakerpins 168 which extend into the path of circulation through the housing.The flow continues upwardly through opening 5a; and the ra .lly inwardlyprojecting lugs provide obstructions for further pulverizing action. Thepulverized particles are then discharged in a current of air through thedischarge opening of the housing. It is to be noted that the upturned 1%on blade 72 also have a pulverizing action on the leaves.

The bottom wall or ring 42 is of imponance in resisting the tendency ofair being blown out around the lower part of the housing and is ofdefinite advantage in increasing the suction action of the impeller indrawing up the leaves, etc.

The rings 42 and 52 define a circular channel-shaped chamber in whichthe leaves, etc., are acted upon by the breaker pins. The leaves, etc.,while relatively light, nevertheless are much more easily andefficiently drawn into and through the housing and discharged therefromwhen broken up into minute particles.

The drawings and the foregoing specification constitute a description ofthe improved leaf mulcher in such full, clear, concise and exact termsas to enable any person skilled in the art to practice the invention,the scope of which is indicated by the appended claims.

What 1 claim as my invention is:

l. A leaf mulcher comprising a carriage movable along the ground, ahousing supported on said carriage, said housing having a generallyvertically extending annular side wall and a generally horizontal bottomwall disposed closely adjacent the ground when said carriage issupported thereon, said bottom wall extending radially inwardly fromsaid side wall adjacent the lower margin of the latter and having acentral inlet opening therein. spaced from said side wall, anothergenerally horizontal wall spaced above said bottom wall, said otherhorizontal wall extending radially inwardly from said side wall andhaving a central discharge opening spaced from said side wall andconcentric with said inlet opening, said vertical and horizontal wallsdefining an annular pulverizing chamber of channel cross-section, bladesmounted in said housing between said horizontal walls and supported forrotation about an axis concentric with said openings, said blades havinga radius approximating the radius of the inlet opening, means forrotating said blades in one direction, certain of said blades having aninclined portion effective to draw air and leaves and the like into saidhousing through the inlet opening and to discharge the same through thedischarge opening when said blades are thus rotated, the rotation ofsaid blades also inducing a circular flow about said axis causing theair and leaves and the like to move radially outwardly into said annularpulverizing chamber by centrifugal force, and breaker elements fixedwithin said annular pulverizing chamber for pulverizing the leaves andthe like circulating in said chamber by direct impingement thereagainst,said pulverizing chamber providing a confining space in which the leavesand the like are held by centrifugal force until pulverized sufficientlyto be carried by the air stream through the discharge opening.

2. The structure as defined in claim 1, including a batile plate in saidhousing spaced between said horizontal walls and extending across saidopenings, the peripheral edge of said baffle plate terminating in spacedrelation to said side wall, said b aille plate assisting in directingthe air and leaves and the like toward said side wall and preventing thesame from bypassing said breaker elements.

3. The structure as defined in claim 2, including additional breakerelements mounted on said other horizontal wall and extending radiallyinwardly oi the discharge opening.

4. The structure as defined in claim 1, in which certain of said bladeshave vertical portions to create turbulence and to beat and therebypulverize leaves and the like circulated through said housing.

